AMSTERDAM (Reuters) - The Dutch government would be obliged to reconsider its position on an EU pact establishing closer ties with Ukraine if it loses an upcoming referendum on the issue, the country's foreign minister said, but he stopped short of saying a "no" vote would scupper the treaty.
The referendum is not binding, but most Dutch parties have said they would respect a rejection by voters, which could plunge the European Union into crisis when tensions with Russia run higher than at any time since the Cold War.
Speaking to reporters on Saturday, Foreign Minister Bert Koenders rejected claims by opponents of the association agreement that it was a first step toward EU membership for war-torn Ukraine, which is battling Moscow-backed rebels in its East.
"The referendum law says the government will have to reconsider if there is a (negative) outcome," he said, adding that he would argue for a 'yes" vote. "I'm not going to say anything about the result, but we will then decide what to do."
The April 6 consultative referendum on the 394-page treaty was triggered after the anti-EU satirical website GeenStijl collected more than 400,000 signatures.
It is one of several challenges faced by the 28-member bloc, which is dealing with an unprecedented migration crisis, sluggish economic growth, a British referendum on membership and a struggle for influence with regional rival Moscow.
Koenders said the treaty would promote stability in Ukraine.
Near where he was speaking, an unruly crowd of several hundred gathered for a demonstration by the Dutch offshoot of German anti-immigration movement Pegida, hoisting Dutch and German flags and anti-Muslim slogans.
"I'm voting 'no'," said Nick, who had traveled from the eastern town of Enschede to participate in the demonstration, at which several arrests were made. "I'm simply against the EU. It's destroying our national identities."
Many voters, worried about the impact of immigration and the EU on their economic security after years of sluggish growth, see the referendum as a rare opportunity to cast a vote against the bloc.
But Russia, which is widely blamed for the 2014 downing of an airliner over Ukraine with 298 aboard, two thirds of them Dutch, may be even more unpopular.
"A vote against the association treaty is a nod to the Kremlin and pro-Russian rebels," wrote columnist Bert Lanting in the Volkskrant newspaper on Saturday. "It is a vote for the people who in all likelihood brought down flight MH-17."
Reporting By Thomas Escritt; Editing by Toby Chopra